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Topic: Coin Storage and Preservation (Read 40641 times)

I started a new business focusing on storage products for coins and other collectibles. The products utilize Intercept Technology, which some of you may be familiar with. While I only have a couple of products to offer at the moment, I hope to add more in the future. I hope you find the information useful and the products beneficial for the long-term storage of your coins. The business and products were developed out of my own need for storage and protection. This is an area which I have great interest in, and a passion for the proper storage and protection of valuable collectibles.

Good luck on starting your new business. The intercept shield products have been tested for many years and proved to be effective in coins and banknotes storage and protection. I use it for high value coins as an extra protection in my bank safety box.

Congratulations on your new business, Chris! I visited your online store already. Do you have smaller packages, say 10 for the smaller slab, so that customers can try out?

Hi Fwang2450,

Thanks for the feedback!!!, much appreciated. The quantities were designed to be cost effective, but I see your point. I should be able to make the change by tomorrow, so pls check back. Obviously the per unit cost will be higher due to the lower quantity.

Thanks for the feedback!!!, much appreciated. The quantities were designed to be cost effective, but I see your point. I should be able to make the change by tomorrow, so pls check back. Obviously the per unit cost will be higher due to the lower quantity.

I noticed yours is the Third Edition. I have the 2nd edition which is a slim hardcover book with 72 pages. Does the third edition have more and newer materials? Where can I buy one, I could not find it on Amazon?

The 2nd edition is also a compilation of 21 articles from 1989 to 2003. It was published in 2004. One thing it can really improve upon is the quality of photos. Since this book is about coin cleaning and preservation, high resolution before & after photos would be really helpful. That was lacking in the 2nd edition, otherwise it is very informative.

I wanted to take a minute and comment on a recent post I saw on another coin chat board. The post discussed a method of storing coins, whereby, coin slabs are placed inside individual poly bags, and then multiple coins in individual poly bags are placed inside a larger poly bag, to which an oxygen (O2) absorber is placed. I am guessing the concept is to remove oxygen from the environment surrounding the coin, which will prevent oxidation (or toning).

This may sound intuitive, given the term "oxidation", unfortunately, the process of oxidation does not require oxygen. In fact, "oxidation" is a process whereby a compound undergoes a reaction that removes an electron. O2 is very stable and has limited impact on the corrosion of coins. Keep in mind, that air is only about 20% O2, 78% nitrogen, and 2% of other stuff.

The primary causes of corrosion are the reaction of metals within the coin with Sulfur and Chlorine. In fact, Sulfur reacts so quickly, that other gases don't stand a chance.

In short, O2 absorbers remove only oxygen. By placing coin slabs in multiple layers of bags only traps harmful gases in many places. Intercept removes all harmful gases including Sulfur and Chlorine and creates a microenvironment.

I urge everyone to take the time and learn about proper storage and preservation. I know many of you have spent significant time researching coins, and if only a fraction of that time is spent researching storage, your investment will be properly protected.

I have a question about the products you are selling. The storage bags are "Corrosion Intercept" bags, not "Intercept Shield" products, right? Can you explain the pros and cons of each type?

Thanks,

Frank

Hi Frank,

Intercept Shield is/was the name of a company that produced products using "Intercept Technology". My understanding is that Intercept Shield no longer produces nor sells Intercept Technology products, I believe as of late last year. You can only find their products, which consist mostly of boxes, etc. in the aftermarket.

Corrosion Intercept is a product within the family of "Intercept Technology". Corrosion Intercept is translucent polyethylene material that is used in light industrial, museum, archive, and retail applications. It meets Cleanroom 100 standards, and is approved for use by NASA.

As a follow-up i want to point out that "Intercept Technology" works best when it is as close as possible to the metal it is protecting. Also it is helpful to minimize air flow. Coin Armour bags are made using 50 percent clear polyethylene and 50 percent Corrosion Intercept, and utilize a zipper seal to restrict future airflow. The front side of the bag is clear to easily identify the coin.

Intercept Shield is/was the name of a company that produced products using "Intercept Technology". My understanding is that Intercept Shield no longer produces nor sells Intercept Technology products, I believe as of late last year. You can only find their products, which consist mostly of boxes, etc. in the aftermarket.

Corrosion Intercept is a product within the family of "Intercept Technology". Corrosion Intercept is translucent polyethylene material that is used in light industrial, museum, archive, and retail applications. It meets Cleanroom 100 standards, and is approved for use by NASA.

Hope this helps.

thanks,Chris

Thanks, Chris. But Weimar White says in his book, for example on page 35, that "the Corrosion Intercept bags mentioned in this article are no longer available and have been replaced by Intercept Shield products". Intercept Shield products are available from dealers listed on their website at: http://www.interceptshield.com/. He seems to favor the Intercept Shield products over the 50/50 Corrosion Intercept bags.

Thanks, Chris. But Weimar White says in his book, for example on page 35, that "the Corrosion Intercept bags mentioned in this article are no longer available and have been replaced by Intercept Shield products". Intercept Shield products are available from dealers listed on their website at: http://www.interceptshield.com/. He seems to favor the Intercept Shield products over the 50/50 Corrosion Intercept bags.

Any comments?

Hi Frank,

The article on page 35 was written in June 2000, and alot has changed since then. If you notice, most dealers are out of stock on almost all "Intercept Shield" products. Pls feel free to contact Intercept Shield.

Thanks, Chris. But Weimar White says in his book, for example on page 35, that "the Corrosion Intercept bags mentioned in this article are no longer available and have been replaced by Intercept Shield products". Intercept Shield products are available from dealers listed on their website at: http://www.interceptshield.com/. He seems to favor the Intercept Shield products over the 50/50 Corrosion Intercept bags.

Any comments?

It is my understanding that both "Corrosion Intercept" and "Intercept Shield" are trademark. They use the same technology developed by Du Pont.

I started a new business focusing on storage products for coins and other collectibles. The products utilize Intercept Technology, which some of you may be familiar with. While I only have a couple of products to offer at the moment, I hope to add more in the future. I hope you find the information useful and the products beneficial for the long-term storage of your coins. The business and products were developed out of my own need for storage and protection. This is an area which I have great interest in, and a passion for the proper storage and protection of valuable collectibles.

Thanks, Chris. Very interesting products. Question on your product description "Expected Corrosion Protection Term: 5 Years" - Do these bags need to be replaced every 5 years? Also, 5 years from the date of manufacture or purchase? Is expiration date indicated on the bags or somewhere? Thanks in advance for clarification.

Thanks, Chris. Very interesting products. Question on your product description "Expected Corrosion Protection Term: 5 Years" - Do these bags need to be replaced every 5 years? Also, 5 years from the date of manufacture or purchase? Is expiration date indicated on the bags or somewhere? Thanks in advance for clarification.

The life expectancy of Corrosion Intercept is from the manufacture date. Unfortunately there is no born on date on the bag, however, the manufacturer has to continuosly source new product for the use in the Electronics, Military, Auto Parts industry. So new Intercept material is being produced continuously.

The actual life of Corrosion Intercept depends upon the environment the coins are stored in. The key here is that Corrosion Intercept is copper in color. As the bag absorbs harmful gases the copper color will turn black. When this happens it is time to replace the bag. So it could be more or less than 5 years depending on storage conditions and the levels of exposure to harmful gases. As an example, I have had samples for about 2 years, and not seen any change is color. While the bag is working, it has not become saturated enought with harmful gases to change color.

Are the coin storage bags intended primarily to prevent corrosion and/or toning of silver coins? Will they help prevent copper and carbon spotting on gold coins? Is there in any value to storing platinum or palladium in these (I have never personally seen toning on these metals)?

Are the coin storage bags intended primarily to prevent corrosion and/or toning of silver coins? Will they help prevent copper and carbon spotting on gold coins? Is there in any value to storing platinum or palladium in these (I have never personally seen toning on these metals)?

Toning and corrosion are used interchangeably, since toning is corrosion. So the answer to your question is yes. There is a lot of information and research on the website regarding the benefits of Corrosion Intercept.

Spots on gold coins result from impurities in the coin that are concentrated during the minting process. Two most common impurities are silver and copper. My understanding is that when corrosive gases corrode the silver and copper, the form spots, so yes Corrosion Intercept should help prevent copper spot from forming or reforming after conservation.

I am not aware of any corrosion issues with platinum or palladium, but at .65/bag, it a small price for protection vs. no protection.

If you put an intercept bag on a slab will it still fit in a Ngc box Any plans on making big bags for the Ngc boxes

I just tested the NGC boxes. Its a little tight, but it will fit. You have to place it in slowly to avoid the bag from tearing.

Regarding larger bags for NGC boxes. I originally answered this question no a couple of posts ago. While there are no plans to make a custom size bag for an NGC box, we should have in stock very soon larger bags designed for graded comics (9 1/2 x 13 3/4). These should fit one maybe two NGC boxes. I will check when the bags arrive.

Intercept Shield products are no longer available however the coin supply stores still have left over stock. So while they may have been available, they are no longer producing this product. Here is an FAQ from ICG website:

Q?Do you still provide the Intercept Shield Holders? A.As of right now, we only have Intercept Shield gaskets for:

FYI, I purchased a few of these, and I can say the overall quality is good. 1668Chris appears to have a nice product here, and his communication and shipping times are top notch. Also of note, Piedfort slabbed coins will fit the smaller bags if you only have a little patience. Two 5oz or 12oz slabbed coins will fit into each of the larger bags. As for prospects of increased protection against corrosion, only time will tell.

While the design might seem relatively simple, it definitely has its challenges in production. However, since I am sort of a perfectionist, I expect no less than 100% consistent quality. This translates into a product that is not only effective and functional, but meets expectations in terms of consistency.

Regarding the effectiveness of Intercept, I uploaded another research article focusing on case studies, whereby companies like Royal Mint of England, Guggenheim, and Raytheon used Intercept to solve their challenges.

Regarding the rim scratches, I recall reading a couple of years ago that NGC does not consider the rim part of the coin. I know tha sounds silly, but I have seen a gold 1998 PF 70UC flower tiger with a sizable rim dent. Regarding the spot, it looks like the coin may have been conserved prior to grading. On the NGC photos you can see the remnants. However from the looks of the eBay photo it appears the spot may be below the surface. In which case the spot will reappear if it comes in contact with harmful gases.

Regarding the rim scratches, I recall reading a couple of years ago that NGC does not consider the rim part of the coin. I know that sounds silly, but I have seen a gold 1998 PF 70UC flower tiger with a sizable rim dent.

Maybe it all depends on the grader and the day of the week. There are many slabbed MCC with the designation "Proof Details" "Rim Damage". Coins that have been dropped receive that designation. I can't imagine them grading a rim-dented coin any higher. I have never seen it. If they have graded it hogher, in my opinion, they shouldn't have!

If you look at the listing it doesn't say anything about rim damage or scratches on the coin. Nor do I see any on the coin. I'm not sure where the idea is coming that the coin has rim scratches or damage. The damage mentioned is on the edge of the SLAB and scratches on the slab. Even the close-up picture of the spot shows a nice scratch that is clearly on the slab since you see the reflection in the coin. In other words coin is likely fine unless it was damaged while in the slab since the slab appears to have been somewhat mistreated. Of course the coin still has the spot and possibly haze like many silver mcc's.

Ahh yea I see what you mean on the date side of the coin. Does look like some decent scratches. They don't show up as well on the seller photos so I wonder how noticeable they are. As far as rims and damage. PCGS and NGC don't downgrade as much for damage in those areas as they do for other areas where distractions are more obvious. I made a post sometime ago on that subject. I'll see if I can dig it up. Damage on this coin looks pretty decent so a 69 could still have been an over grade if the damage is as obvious as it appears to be on the ngc photos.

Most of the pollution is coal plants to make electricity. We have a coal plant in Florida that produces very little pollution but they are expensive to build. So the technology is there. China should sell their older MCC to us, on this forum, to raise capitol to upgrade the coal plants! Win Win situation (for us anyhow)..........

I thought it would be helpful to post both the NGC/PCGS guarantees here, including their exceptions (as they relate to storage and preservation) for reference purposes:

NGC:

If, in NGC’s sole opinion, the grade determined under such review is ultimately lower than the grade originally assigned, NGC will offer one of the following three remedies:

NGC shall purchase the coin from the submitter at its determination of the current market value (see below) for an example of that coin which is correctly graded at the original grade level assigned.

NGC shall exchange the coin in question with an equivalent coin at the original higher grade.

NGC shall return the coin to the submitter at the correct lower grade and pay the difference between the current fair market value (see below) of the coin at the newly established grade and the current fair market value of the grade originally assigned to such coin.

NGC Exception:

The NGC Coin Grading Guarantee does not apply to coins exhibiting environmental deterioration subsequent to certification. These issues include but are not limited to spotting, hazing, PVC, and corrosion.

PCGS:

If the grade determined under such "Guarantee Resubmission" procedures is lower than the grade originally assigned to the coin, or if the coin is found to be misattributed, non-authentic, PCGS shall pay the current market value for the coin in question at the originally assigned grade, or at the owner of the coin's option, the difference between the current market value for the coin in question at the newly established grade and the current market value of the coin in question at the grade originally assigned. PCGS will also refund the regrading fee and postage and insurance costs incurred by the coin owner in sending the coin to PCGS. IT IS UNDERSTOOD THAT PCGS WILL BE THE SOLE DETERMINER OF THE CURRENT MARKET VALUE OF THE COIN AND THAT CURRENT MARKET VALUE IS DEFINED AS DEALER REPLACEMENT VALUE, I.E. THE PRICE A DEALER WOULD MOST LIKELY HAVE TO PAY TO REPLACE THE COIN.

PCGS Exception:

Further, this guarantee shall not apply to coins exhibiting environmental deterioration subsequent to certification, including spotting on modern silver coins.

Coins exhibiting environmental deterioration. The PCGS Guarantee does not apply to coins exhibiting environmental deterioration subsequent to PCGS grading and encapsulation. This deterioration may include, but is not limited to, spotting, hazing, PVC contamination, and corrosion.

If you notice, both exceptions include language "including but not limited to". Having been drafting, reviewing and interpreting legal documents for a very long time, this language is used as catch all phrase and does not limit either PCGS or NGC to issues that are only enumerated in the exception (i.e., kitchen sink approach)

Exactly how these exceptions are applied in practice is anyone's guess, but the key is that both PCGS and NGC are the sole determiner in the market value associated with the guarantee, regardless of what you paid for the coin or think it is worth.

1) I will have a table at the Whitman Coin Expo in Philadelphia in September. If anyone is around please feel free to stop by and say hi

2) We now have boxes to complement our storage bags. They are compact, heavy duty, and lined with acid free paper. They will hold 15 slabs and are available in our store

3) There will be a price increase on the small coin bags in September...not sure of the exact date. We are moving away from the introductory price, plus we have higher material and manufacturing costs

4) Finally, I have a limited number of "irregular" small coin bags. The seals are perfect and the zipper is perfect, however they were made with one or two millimeters of extra Intercept, so they don't look perfect for retail sale. The bags are the same size as the perfect ones, but they look a little wavy due to the extra material. Actually once you put a slab inside you won't even know the difference. Price is .50/bag minimum order is 50 bags plus shipping (Domestic only, sorry no International orders). First come first serve. Please contact me via email from the website. I don't monitor PMs on the board that often.

I saw this on another chat board I belong to and thought I would post it. It is amazing the great lengths that someone will take to protect their coins. I wonder if this person actually created this box ...either way they put alot of thought into it :

"If you really wanted to put your coins away for long term storage purposes, you would put your slabbed coins into a metal box with refrigeration fittings on it. Refrigeration fittings or hardware are rated for operating in a vacuum. It would require some customization to be done, in order for refrigeration service ports to be added to the metal box but once you have a sealed box you would be best served by using a vacuum pump to pull the box into a deep vaccum meaning sub 500 microns. You can then break the vacuum by introducing a small volume of dry nitrogen inside the box. The box will still be in a slight vacuum and it will also contain the best desiccant one could hope for "

PS. I will be at table 112 at the Philly Whitman Coin Expo September 19-21st....all the eastcoasters pls feel free to stop by.

This coin appears to have developed white spots on the reverse and some staining along the rim after grading. It is now far from a perfect 70 vs. the NGC file photo. Proper storage is key to any collection (whether long-term or short-term)...it does not matter if you are a collector, investor or dealer.

What do you think about the need for "proper storage" and care for one's gold coins as opposed to one's silver coins? Silver seems much more reactive/corrosive and prone to developing problems over time. In fact, that is one of the reasons I am beginning to divest from my silver MCC purchases of the past few years . . . I'm scared they'll no longer be worth what I paid for them when they develop problems the process for which I cannot reverse. Do you see this happening with gold coins as well?

Every coin should be properly stored. The same harmful gases that cause a silver coin to tone or spot will also cause a gold coin to develop copper spots or tone. While the impact may not be the same with gold, since copper spots can be removed, you still encounter a major dilema. Keep in mind that gold contains impurities (mainly silver and copper). When exposed to harmful gases these impurities will corrode and cause spots.

If the coin is slabbed and graded, then develops copper spots over time due to improper storage, it most likely is not worthy of the same original grade. You can decide to do nothing which may impact value over time, or resubmit for appearance review or conservation. The risk you run is you might not get back the same original grade...this is the issue currently facing Birdman in a previous thread.

Also, here is a pic a platinum coin that developed corrosion. This coin was auctioned by Stacks over the summer. The appearance in my mind is horrible, and not something that I would choose to bid on. Eye appeal is everything in coins.

Chris-That's a very interesting platinum example you posted above. Have you seen this phenomenon frequently in platinum before? In my personal experience that coin would qualify as seriously exceptional. Also, have you noted palladium to have similar issues?

The December 17, 2012 issue of Coin World had an article describing the Mint's acknowledgement of the "white spots" problem for modern silver coins, especially the .999 American Silver Eagles. In the article it states,

"During her less then 18 months as the U.S. Mint's quality division chief, Stacy Kelley-Scherer has focused her attention on a problem that has plagued the American Silver Eagle silver bullion coin almost since its 1986 inception – spots. So far, a solution that prevents spotting from occurring has eluded Mint officials... Each year of the program, collectors and dealers of the American Eagle silver dollars have reported spots or blotches on the obverse and reverse, on all finishes – bullion, Proof and Uncirculated – and on coins from all Mints. The spotting is random and can appear as a single spot, multiple spots crossing the field and devices, or in large blotches or patches consuming significant portions of a coin's design."

The article illustrated spotted Silver Eagles that had been graded by Numismatic Guaranty Corp. (NGC). But the problem is not limited to NGC or any other grading service. At PCGS, we have received Silver Eagles in sealed Mint boxes (the 500 once green "monster boxes") and opened them to find coins that have already spotted. We have also graded spot-free coins, sent them to customers, and then had them returned to us months later after they had developed spots. There seems to be no rhyme or reason as to why some coins spot and some don't. But it is clearly something that is happening at the U.S. Mint.

The problem is also not limited to Silver Eagles or coins from the U.S. Mint. We have seen the same spotting problem on modern U.S. silver commemoratives and modern coins from other Mints such as Canada, China, and Australia. Our feeling is that it has something to do with the .999 silver composition, as the earlier pre-1965 90% silver coins seldom spot. However, it could also have something to do with the way the planchets are prepared or washed. We are not sure of the cause of the spotting, and apparently neither are the Mints of the world.

PCGS Modern Silver Coin Spot Policy

When initially grading modern silver issues, PCGS will deduct for spots that are already evident. If coins spot after they are graded by PCGS, they are not covered by the terms of the PCGS grading guarantee. If you would like us to try to remove spots from your coins by "dipping" them, we may be able to do that. It is our experience that spots on proof Silver Eagles can be removed in about 80% of the cases, but spots on Mint State Silver Eagles will only come off approximately 10% to 25% of the time. We launched a Restoration Service on January 2, 2013 and for a fee (grading fee plus 4% of the value) we will remove spots, unattractive toning and other imperfections. However, this fee would be excessive for most modern silver issues so as a service to our customers, we will have a spot removal service for modern silver coins available beginning April 1, 2013. We are only charging a flat fee of $5 for spot removal on modern silver coins. Note that we cannot guarantee whether our spot removal attempt will be successful. If the spots do not come out, we will still reholder you coin in its original grade. It will just be a spotted coin of that grade. We anticipate that a two tier market (spot-free and spotted) will develop, much as it has in the past 10 years or so in the U.S. generic gold market. For further information about our spot removal service, contact PCGS Customer Service after April 1, 2013.

When I first read this last night I was sort of indifferent to the "spot removal" service. The cost is only $5. However I think this service is actually a disservice to the collector, for several reasons.

Based upon my experience and research, PCGS slabs tend to spot more so than NGC slabs. Is PCGS recognizing this by providing a spot removal service? Also, we know that a spot existing at the time of grading will reduce the grade. The fact that PCGS will remove a 70 coin from its holder, try and remove spots and if unsuccessful, will place the coin back in its holder with its original grade, I think is wrong;

"If the spots do not come out, we will still reholder you coin in its original grade. It will just be a spotted coin of that grade"

The coin with a spot is no longer a 70. Why PCGS would reholder a coin with a spot and provide the same grade is a disservice to the unsuspecting collector. If they are to remove a coin from the holder and provide some level of conservation, the coin should be regraded. Will they provide a 70 grade label with a "spot removal" reference??

Many new collectors might be unaware of an experienced dealer trying to sell 70 grade coins with spots that PCGS tried to remove. The new collector might think a 70 is a 70 no matter what.

Also, how many times can someone submit the same coin for spot removal? Finally, the PCGS grade guarantee does not cover environmental damage, which a spot would fall under. Therefore the unsuspecting collector could not even collect on the guarantee!!

IMO, PCGS is courageous in coming out with this policy. Regarding white spots, PCGS (and NGC) is in a difficult position: it is a ticking time defect that can happen anytime, nobody seems to understand it and it is really not the grading company's fault. PCGS can raise the grading fee or refuse to grade 0.999 silver coins, but that's bad for business. PCGS already refused to honor the grade guarantee w.r.t white spots which no doubt upset many collectors already. Reading between the lines, PCGS seems to treat the white spots as a "toning" issue, i.e., white spots, like toning, do not affect grade; it is cosmetic, so if collectors want spots removed, PCGS will do it but their grades remain the same whether or not the spot removal were successful. I think it is a tough sell and PCGS likely will get beat up badly over this. Yet I give PCGS kudos for taking a public stand on this difficult issue.

Reading between the lines, PCGS seems to treat the white spots as a "toning" issue, i.e., white spots, like toning, do not affect grade; it is cosmetic, so if collectors want spots removed, PCGS will do it but their grades remain the same whether or not the spot removal were successful.

I have to disagree with the above statement. PCGS stated in their policy: "When initially grading modern silver issues, PCGS will deduct for spots that are already evident"

This issue I have is that if a coin develops spots after grading, it should no longer be worthy of a 70 grade (consistent with PCGS policy). If the coin is resubmitted for any type of conservation the coin should be regraded. Many things can happen to a coin once it is removed from its holder. Apart from the obvious finger prints, dropping etc., the coin is also exposed once again to environmental factors. The fact that PCGS retains a 70 grade for spots that cannot be removed is unbelievable. I only hope that the slab has a special label indicating this.

Personally, once I receive a 70 back from grading, I never ever resubmit, not even for a label change for variety attribution. The less hands that touch a 70 the better.

Here is a link to an excellent research paper discussing the impurities in gold. Generally, silver ranks as the highest impurity. This should give some clues as to why spots form on gold coins that are exposed to harmful gases. Also the research paper discussed how impurities will congregate into one area during the refining process. This will also help explain why some coins only experience spots that are grouped together, as opposed to covering the entire surface....yes, some coins are covered in spots, but many only have one or two.

Chris-Do I understand you correctly in that you are implying the cause of this coin's atypically and ridiculously impaired "PF69" surface is secondary to improper storage techniques? Would you mind quoting some of the volumes that this coin speaks of as evidence of this implication, or do you just have a photo of an impaired coin and are theorizing that the impairment is secondary to storage conditions? Please be precise.

Was this coin conserved by NCS prior to grading? I'm primarily questioning the pattern of the toning. It almost seems like it formed in a pattern/shape that would be left by some type of residue left over from the evaporation of a liquid on the surface of the coin. What I'm trying to say is that it may not be the storage conditions that were the proximate cause of this change in condition over such a (relatively) short period of time. I personally doubt whether even a unprotected silver coin kept in a herpaterium would look that toned after just two years... Something else is going on in this particular instance besides (or in addition to) poor storage conditions, don't you think?

Was this coin conserved by NCS prior to grading? I'm primarily questioning the pattern of the toning. It almost seems like it formed in a pattern/shape that would be left by some type of residue left over from the evaporation of a liquid on the surface of the coin.

The holder is typical for coin graded in China during the show. IMO, the significant degradation of surface was caused by improper handling during the grading and poor storage condition may accelerate the degradation process.

Chris-Do I understand you correctly in that you are implying the cause of this coin's atypically and ridiculously impaired "PF69" surface is secondary to improper storage techniques? Would you mind quoting some of the volumes that this coin speaks of as evidence of this implication, or do you just have a photo of an impaired coin and are theorizing that the impairment is secondary to storage conditions? Please be precise.

It is clear from the NGC file photo that this coin exhibited zero corrosion shortly after it was graded which was the basis for my statement. Whether it was conserved or graded during a show, I have no idea. But I do know that NGC holders are not air-tight. Here is a quote directly from NGC's website. This is a similar statement by PCGS.

Q. After encapsulation, can the appearance of a coin change over time?

A. Yes. In independent testing, the NGC security holder has been proven as the most effective grading service holder on the market today in minimizing the effects of oxidation. Even so, the NGC holder is not 100% airtight. Therefore oxidation, a normal process where air reacts with the surface of a coin, can continue after encapsulation. To further limit environmental hazards, we recommend storing your coins in a temperature-controlled, low-humidity area such as a bank safety deposit box. Be sure to check with your bank for rules and regulations concerning the storage of these items.

As a result, harmful gases (what NGC refers to as "air", however it is not "air" that is the cause, since O2 is a very stable gas) can and will penetrate the holder and react with the surface of a silver coin. Also, corrosion can take different forms, especially on silver since it is a very reactive metal.

Finally, I am advocating that everyone should take time and understand the importance of proper storage techniques. As much time as we all invest in researching coins, we should spend just as much understanding how to properly care for them.

Here is an excellent write-up on Intercept Technology being used for protection of valuable museum collections:

The initial Intercept Technology™ customer used the material to protect wafers for electronics, the second customer was the Getty Museum and the third was a major Mint to protect incoming Silver. Intercept has long been used and regarded as an ideal material for Museum Storage and for protection of materials being archived.

When Bell Labs developed the Intercept Technology™ they ensured that the harmful additives and non-essential fillers used in plastics were not incorporated into the Intercept Technology™. Some of these are, various volatile agents, anti-block agents (silica is added to typical plastics to keep the film from sticking together - silica is abrasive and often produces plastics that can cause surface scratches), or other non-essentials or fillers. Intercept materials start with reactor grade, barefoot polymers. We react the Copper into the polymer, binding it so that it is not free to migrate. We do not add in volatile components or anti-block agents. Intercept is safe for the storage of even the most sensitive items and has tested to pass PAT and other archival tests.

Museums have used Intercept film, wraps, totes and bags for the storage of their collections that are sensitive to corrosion / degradation / pollution. Intercept film is used as backing material for framed items to keep the pollution away from the items within the frame. Additionally Intercept Active Filtration (Intercept saturated foam with a fan unit) has been used to protect museum cases, jewelry cases and small storage areas. The Intercept reacts with and permanently neutralizes the active pollutants in Museum or Jewelry cases. When Intercept is used as a wrap or bag, it reacts with these gases, cleansing the inside environment and then acts as a barrier prevent reintroduction of these gases. Museums have utilized Corrosion Intercept® films and products because they do no harm, and because the Copper color of Corrosion Intercept® (CI) changes hue as it reacts with and neutralizes pollutant gases, providing a visual assurance that the Intercept is working. When the CI color turns dark grey or white (for exposure to Nitrous gases) then it is time to change the package.

Intercept provides protection against the three major causes of degradation to CD’s and digital data –ESD damage, Ozone and UV. The RIBS MVTR product line has also been successfully used to provide protection against mold and mildew, to react with and permanently neutralize corrosive pollutants in the environment as well as provide the moisture barrier protection of foil, in conjunction with the ability to absorb organic components due to its buried carbon layer.

Here is the quick video showing the opening of the 1795 time capsule from Paul Revere and Sam Adams. If you notice the Boston Museum of Fine Arts is using Corrosion Intercept to place most of the items on:

Here is another coin that developed significant issues post grading. It is unfortunate since it was a 70.

If the likely cause of this condition is the air that is trapped inside the slab, then NGC should be 100% responsible. I know that it was not submitted in that condition. Furthermore, the owner may have had this coin unslabbed for many years prior to submitting and their were no issues. If true, again, fault of NGC. Has anyone seen video of NGC flushing-out the inside of the slab with inert gas upon sealing? I think that is all part of their BS and hype.

If the likely cause of this condition is the air that is trapped inside the slab, then NGC should be 100% responsible. I know that it was not submitted in that condition. Furthermore, the owner may have had this coin unslabbed for many years prior to submitting and their were no issues. If true, again, fault of NGC. Has anyone seen video of NGC flushing-out the inside of the slab with inert gas upon sealing? I think that is all part of their BS and hype.

Ngc blames those coins that are white spotted on the mint and now excludes those coins from warranty

I wrapped my 2016 panda trays into plastic foil like you use it for foods. Dunno if it helps preventing from spots?!?!?!

Another solution would be to vaccumseal them, a lot of german collectors do it, but for me this is overreacting, since i believe the original mint capsules are also tight.

I used the large coin armour bag (that was designed for storing comics) to store my coin trays. You can fit in three coin trays in each bag. Slide in one tray at a time. I posted some photos somewhere in this forum. I will try to find the link.

Vacuum sealing can exclude water from the trays but does not prevent entry of culprit gases into the bag. The coin armour bag is reputed to prevent gas entry as well as neutralize the gases already entrapped in the bag.

I'm going to sound negative but o well. If silver one ounce panda coins cost 15 plus dollars over spot per ounce raw then how many more years do they need to get this milk spotting thing cleared up. As consumers or should I say investors, shouldn't we demand more quality before investing any more. That is why I no longer buy the 1 ounce silver pandas. You could drop some serious money to buy a great looking 70 and then a couple of years later you have a worthless milkey spotted mess. And I know it's not just Pandas. But if Pandas they lead in cost premium over spot then this needs to be corrected. Sorry it's just frustrating that we need to drop more money on special protection to protect something that is already in a protected holder. Are we investing in protection equipment or are we investing in coins? I not trying to step on anyone's feelings it just frustrating wondering how long the next ms70 will stay ms70. To me a true ms70 should not contain any spotting and I know all buyers would rather buy a spot free ms70 over a spotty ms70

I stopped collecting silver pandas and focused primarily on gold and this was one of the reasons. I had a nice collection of silver pandas but almost all of them developed spotting or milky haze after NGC grading. I got sick of dealing with it and dumped all of them and put the money into gold pandas. I can't say with certainty that it was NGC's doing, but I can say that none of the silver pandas that I kept in OMP developed spots - the only ones that developed milk spotting were the ones that NGC graded. I still have a couple dozen silver pandas in OMP and none of them have spotting. Paul4444 is correct in that pandas aren't the only coins susceptible to milk spotting - I've seen many Perth mint coins develop it too, and I recall other collectors talking about silver US eagles with this problem. I still buy and hold silver, but only as a low-premium bullion holding. I've had this conversation with other forum members - I don't mind copper spotting one bit, but if I'm going to have to accept milk spots then I won't consider silver coins as anything more than bullion.

Sorry it's just frustrating that we need to drop more money on special protection to protect something that is already in a protected holder. Are we investing in protection equipment or are we investing in coins?

I understand your frustration but there is a significant difference btw white spots and corrosion. White spots are the results of residue left on a coins surface during the minting process. Exposure to air reveals these spots. Corrosion is the result of atmospheric gases ,that exist everywhere, that react with the coins surface. Silver is a very reactive metal and can be subject to significant corrosion if not properly protected. Also NGC never claims to protect a coin from atmospheric corrosion. They are a grading company. Finally protection from corrosion is a minor cost in comparison to the cost of the coin.

I understand your frustration but there is a significant difference btw white spots and corrosion. White spots are the results of residue left on a coins surface during the minting process. Exposure to air reveals these spots. Corrosion is the result of atmospheric gases ,that exist everywhere, that react with the coins surface. Silver is a very reactive metal and can be subject to significant corrosion if not properly protected. Also NGC never claims to protect a coin from atmospheric corrosion. They are a grading company. Finally protection from corrosion is a minor cost in comparison to the cost of the coin.

+1 Wise advice for those who are investors or worried about losing value in their collection. As a collector of silver Chinese culture and art pieces I have had to come to terms with these potential losses and buy accordingly.

I stopped collecting silver pandas and focused primarily on gold and this was one of the reasons. I had a nice collection of silver pandas but almost all of them developed spotting or milky haze after NGC grading. I got sick of dealing with it and dumped all of them and put the money into gold pandas. I can't say with certainty that it was NGC's doing, but I can say that none of the silver pandas that I kept in OMP developed spots - the only ones that developed milk spotting were the ones that NGC graded. I still have a couple dozen silver pandas in OMP and none of them have spotting. Paul4444 is correct in that pandas aren't the only coins susceptible to milk spotting - I've seen many Perth mint coins develop it too, and I recall other collectors talking about silver US eagles with this problem. I still buy and hold silver, but only as a low-premium bullion holding. I've had this conversation with other forum members - I don't mind copper spotting one bit, but if I'm going to have to accept milk spots then I won't consider silver coins as anything more than bullion.

I use the intercept bags. They are a great product. I just wish the mints would add another medal to the 1 ounce of silver to reduce this chemical reaction. If I owned a mint I would want the best product leaving my building. Quality control. I thought at this point the mints would have addressed this issue. I love the panda 1989 design but I want the 2016 quality.

This form of corrosion is caused by the mint’s manufacturing process and can develop anytime, from right after striking to many years later. NCS cannot remove these unpredictable spots, but rest assured that none of NCS’s techniques cause them, either.

White “milk” spots can negatively impact a coin’s grade at NGC, but NGC cannot be liable for spots that occur after encapsulation. The NGC Guarantee specifically excludes coins “exhibiting environmental deterioration subsequent to certification. These issues include but are not limited to spotting, hazing, PVC and corrosion.”

I use the intercept bags. They are a great product. I just wish the mints would add another medal to the 1 ounce of silver to reduce this chemical reaction. If I owned a mint I would want the best product leaving my building. Quality control. I thought at this point the mints would have addressed this issue. I love the panda 1989 design but I want the 2016 quality

Seems like the 2016 Silver Panda coin is not immune from the white spot problem. Attached is the photo of a 30g coin I saw on eBay recently.

NBM, have you not been using intercept technology to store you material? I hope I would have advised you to do so, but cannot remember. We've been at this for a long time . . .

Of course I take precautions, I'm not sure what gave you that impression. My comment was actually about our conversations and your decision several years back to move to gold away from silver. At that time I had some choices to make. Collecting gold historical & cultural issues is for the most part a little beyond what I want to spend whereas the silver pieces are pretty obtainable... BUT one must take precautions to preserve with the understanding that all may be for nought if WSOD come knocking.Better?